Matrilin-2 Is a Widely Distributed Extracellular Matrix Protein and a Potential Biomarker in the Early Stage of Osteoarthritis in Articular Cartilage

Figure 3

Inherent expression of matrilin-2 in cartilage and bone. Newborn and adult mouse tibiae were investigated by immunohistochemistry. The positive signals localized at the cartilage of newborn mouse tibia including resting, proliferating, hypertrophic zone, and perichondrium, periosteum, new bone marrow, and ligaments (a and b). The strongest signal localized in hypertrophic chondrocytes. In the adult mice, matrilin-2 expression level is much decreased. The positive signal mainly located in articular cartilage and hypertrophic chondrocytes (c, d, and e). There are no positive signals detectable in other zones of cartilage and bone marrow. Bar, 350 μm in (a); 100 μm in (b), (d), and (e); 1 mm in (c).